#include<bits/stdc++.h>

using namespace std;
using ll = long long;
#define endl '\n'

template<typename T=int>
inline T read() {
    T x;
    cin >> x;
    return x;
}

double foo() {
    string tok;
    cin >> tok;
    double x;
    istringstream iss(tok);
    if (iss >> x) {
        return x;
    }
    double a = foo();
    double b = foo();
    double c = 0;
    switch (tok[0]) {
        case '+':
            c = (a + b);
            break;
        case '-':
            c = (a - b);
            break;
        case '*':
            c = (a * b);
            break;
        case '/':
            c = (a / b);
            break;
        default:
            break;
    }
    return c;
}

int main() {

    cout << fixed << setprecision(2) << foo();


    return 0;
}
